I am wondering if there is any scientific evidence that abiogenesis occurred on planet earth, at some stage in its history.
If so, what is it?
Well, we’re here for one. Life had to begin somewhere, so it’s somewhat more plausible that it did here, than the more convoluted path of starting elsewhere and then arriving here by a great stroke of luck.
And we know that the chemistry of the early Earth contained building blocks that would allow it to happen - simple organic molecules and a source of energy.
Those are scientific evidence. If you want physical evidence, like fossils, then I don’t think we’ll ever have that because chains of molecules don’t leave fossils.
Is that scientific evidence of abiogenesis?
Wikipedia (yes, Wikipedia) begins it’s entry on abiogenesis as:
Is the fact that “we’re here” scientific evidence that our origins as a life form are purely material?
Actually yes…there is new scientific evidence that abiogenesis is what happened on earth. While such things cannot ever be proven 100% (short of getting a time machine to go back and watch it happening) this lends credence that it at least can occur.
Well, yes and no.
Given that we are here one can wonder where we came from.
If you hold that God magicked us into existence then the discussion ends there.
If you hold that we evolved from “lower” life forms then one must assume that abiogenesis occurred. If you keep winding the clock back to simpler and simpler life forms at some point you get to a first step. Even if aliens plopped us here we still have a first cause somewhere else.
So, if we are here, then abiogensis had to occur or a Supreme Being willed us into existence.
I cannot see any other option.
Science doesn’t deal with non-material, so yes.
It seems to me your real question is, “Is there any scientific proof that God did not create life?”
If not, could you clarify your question?
As far as abiogenesis, there is life now, and at some point there was no life. Somehow there was a transition from no life to life. Ergo abiogenesis.
I suppose one can argue what is meant by “abiogenesis” and whether that excludes or includes actions by supernatural agents (i.e. gods).
From a scientific standpoint, the role of a god, if any, is unmeasurable, indeterminable, and irrelevant. Even if God did it, science is more relevant to how God did it than if God did it.
It is possible that abiogensis did not occur on earth though and it does not require Space Aliens or Supernatural Creation. An alternative suggested was that earliest life did originate off planet and came to the Earth via spores or inside a rock. I don’t find this likely but I do recall it being discuss on Cosmos, the Carl Sagan PBS series. I don’t have a good cite for this but of course Google offers many poor cites.
You still have abiogenesis somewhere. Turn the clock back far enough and you have the universe 1 second post Big Bang. It is safe to say there was nothing living then. So, somewhere, somewhen life popped out of inanimate matter of its own accord. If that happened elsewhere and then traveled to earth fine.
ETA: Triple simulpost…cool!
Since there are no gods or other supernatural critters to wish us into being, we had to come from somewhere. It’s either abiogenesis on Earth, or panspermia, which requires abiogenesis elsewhere.
ETA: Interesting simulpost.
Another wrinkle is that abiogenesis may not have occurred on our planet, but it may have occurred somewhere else in our solar system and then seeded life on earth. But that just pushes the question back to another planet.
ETA: Drat. Too late.
Physical evidence for abiogenesis on Earth is elusive, and will probably remain so for a variety of reasons. The Earth has a very active surface, and rocks are continuously processed over long periods of time due to plate tectonics. Consequently, very ancient rocks from the period in which abiogenesis likely occurred are very rare (some time between 3.5 billion years ago, the age of the as-yet oldest unambiguously identifiable fossil evidence of life, and 4.5 billion years ago, the age of the Earth).
Another complicating factor is that the Earth may have experienced a relatively brief but intense period of heavy meteoroid bombardment at about 3.9 billion years ago called the Late Heavy Bombardment. If life had begun before the LHB, then the bombardment may have obliterated much of the evidence. Incidentally, there have been no rocks on Earth discovered so far that date older than 3.9 billion years, though there are a handful of hardy minerals called zircons that have been discovered that are as old as about 4.3 billion years.
Also, it’s not clear what kind of evidence the abiogenesis process would leave behind. There have been some claims of unusual isotope ratios in very ancient rocks from about 3.8 billion years ago that may indicate the traces of early life, but this evidence is ambiguous. Organic molecules just don’t fossilize very well.
Me neither. Life adapted to a completely alien environment just up and hopping a few million miles over to Earth, and being able to survive all that? I’d put my money on home-grown life.
Well, since we know that abiogenesis can happen (i.e. we know that there is at least one specific way to get life from non-living material), and we don’t know of any other possible ways to create life from non-life (which means, we don’t know that god can create life, since we don’t know if he exists, or is even possible to exist), our being here is scientific evidence for abiogenesis, yes, in the same way that a river is evidence for a spring somewhere upstream.
That definition of abiogenesis does not exclude supernatural methods. At some point, there was no life and now there is. So it’s a scientific fact that abiogenesis occurred at least once.
It’s a different question of what theory of abiogenesis is correct. That is, what were the specific circumstances and mechanisms that best explain the fact that there is now life when there was once none. If the answer is simply “God did it”, then no scientific theory will be supportable. If not, then science will produce theories to explain it.
First, it is evidence, not proof. Just as in a criminal trial the fact that someone was seen near the scene of crime is evidence in the case against them, but not proof. Abiogenesis is not anything we are ever going to completely prove because it would have been a chain of events that occurred so long ago and would have left no direct traces (such as fossils). So what does that leave us. We exist, that is one piece of evidence. We have a fairly good idea when it would have happened and what the conditions were like at the time. We have proven in a labthat material needed could have been produced by natural processes in that environment. And we have proven in a lab that such materials can become self replicating, and can evolve. Will we ever be able to say that on some specific date at some specific place a specific process occurred and life on earth began? Most probably not. But we can prove it could have happened by certain process and determine which places and times are the most likely candidates. This may also help us in the future because if we can figure out how likely it is that on any earth like planet life arose.
Jonathan
ETA: There can never be proof that any event, up to and including me posting this, was not done by a supernatural omnipotent deity. All we can do is prove that it could have happened with out one.
What about Bob?
Well, our immediate ancestors had purely material origins, and their ancestors, and so on, all the way back as far as we are able to peer into history. Nothing has ever been shown to simply pop into existence, either at the whim of magicians or otherwise. There are many plausible ways abiogenesis could have occurred naturally, and zero plausible ways that something can magically appear out of thin air.
That isn’t proof, but the “Magic Man” theory faces a major uphill battle against science, and prospects aren’t looking good.
Is the OP suggesting that magically breathing life into clay isn’t Abiogenesis? 
pan(fried)spermia I believe is more apt.